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Effective Ways of Instructing Communicative Language Activities in English Classes
Get PDF室蘭工業大学・言語科学国際交流ユニットでは、令和3 年度から4 年度にかけての研究計画として「効果的なコミュニケーション指導の有り方」を共通テーマに設定し、令和4 年度には教室対面授業、オンライン授業、ハイブリッド・ハイフレックス授業の三つの異なる授業形態を実施する中で、①学生と教員との距離感、②授業形態の違いによる学習量、③遠隔機器の有効な活用法の三つの課題にユニットとして取り組んできた。遠隔授業と対面教室授業を併用する中で、多くの教員が、様々な遠隔授業ツールの便利さ・有効性と、対面教室授業ならではの強み・持ち味の両方を実感することとなった。journal articl
Micellar Mechanisms for Desymmetrization Reactions in Aqueous Media
Get PDFWater-mediated organic reactions significantly contribute to the protection of the environment. Desymmetrization reactions, which convert only one of the identical functional groups within one molecule, are cost-effective because of the low cost of the starting materials. In combination with these two merits, highly efficient and practical selective monohydrolysis reactions of symmetric diesters were previously reported. The products of these reactions are versatile building blocks. The mechanisms of this reaction are hypothesized to proceed through micellar aggregates in which the hydrophilic carboxylate anions formed by monohydrolysis are directed outward and the remaining hydrophobic groups are directed inward in governing the selectivities. Here, dynamic light scattering and electrophoretic light scattering experiments were performed for detection of the key intermediates in the reaction. These experiments revealed the existence of aggregates with negative charges on the surface in the mainly aqueous media, supporting the reaction mechanisms that control the high selectivities.journal articl
Cyclic Behavior of Interfaces for Seismically Retrofitted RC Buildings
Get PDFIn seismically retrofitted reinforced concrete (RC) structures, new members are connected to existing members using interfaces with roughened surfaces and post-installed dowel bars. During an earthquake, the interfaces are subjected to cyclic shear and normal stresses. Therefore, the structural design of interfaces is essential. In a previous study, normal and shear loads were applied to interface specimens. Moreover, a shear strength estimation method was proposed; however, the cyclic behavior was not discussed. This paper presents a cyclic model of the roughened surface in retrofitted RC structures. First, an envelope model was constructed using the previous shear strength estimation method and Saenz model, a constitutive law of concrete. Subsequently, the cyclic rules were modeled. Moreover, a previous dowel model was incorporated into the proposed cyclic model to estimate the test results. Finally, the proposed model provided reasonably estimated test results; the average ratio of the test results to the model results was 1.04. In addition, as δ increased, the effect of the dowel bar intensified in terms of shear.journal articl
降雨と地震動を受ける火山灰盛土の安定性評価
Get PDF室蘭工業大学Muroran Institute of Technology博士（工学）近年，我が国では，予想をはるかに超える集中豪雨によって発生する斜面崩壊，地すべり，土石流などに起因する土砂災害が頻発しており，防災・減災に向けた総合的な対策が求められている．また，我が国は地震大国でもあり， 2018 年 9 月に発生した北海道胆振東部地震では，甚大な地盤災害を経験した．この北海道胆振東部地震の災害では，降雨との複合地盤災害が指摘されており，地震前に通過した台風 21 号の降雨が斜面崩壊に影響を及ぼした可能性が指摘されている．本研究は，降雨と地震動の複合外力条件下で，火山灰粗粒土から構築された盛土の力学 的挙動を調査し，その安定性評価について検討している．本目的を達成するために，一連の1g 場模型実験が，降雨を再現するためのスプレーノズルと地震動を再現するための振動載荷装置を用いて行われている．用いた試料は，先の胆振東部地震により液状化した札幌市里塚地区の住宅盛土の土質材料と同噴出源である駒岡火山灰質土であり， 3 種類の細粒分含有量 と 2 種類の初期含水比 最適含水比に比べ，乾燥側と湿潤側のケース の条件の下で試験が実施されている．得られた結果から，地震前の先行降雨はその後の地震に対する盛土の不安定化に大きな影響を及ぼすこと，また，盛土内に含まれる細粒分含有量の大小は斜面崩壊に大きな影響を与え，降雨と地震の単独または複合条件下の火山灰盛土の安定性を議論する上では十分に考慮しなければならないことが示されている．加えて，同じ締固め度では，火山灰盛土の浸透性は細粒分含有量の増加とともに減少し，先行降雨を受けた火山灰盛土の耐震性では細粒分が多いほどそれが高くなることが示されている．しかしながら，細粒分含有量が 27%を超えると，この耐震強度 の増加は顕著ではない．また，盛土構築時の初期含水量の違いは，降雨や地震による盛土の力学的挙動，浸透特性，崩壊現象に変化を与え，最適含水量の湿潤側における透水性は，細粒分が多く含まれている場合では乾燥側よりも小さく，対照的に，乾燥側で締固められた盛土では，先行降雨による同じせん断ひずみ条件下において，その後の地震に対する抵抗力が低くなることが示されている．このように盛土が複合的な要因で崩壊に至る場合，先行するせん断ひずみが同程度であっても，地震と降雨の順序が異なること，斜面の安定性が異なることが定量的に示されている．最後に，過去に行われた現地計測結果から斜面内の含水量の変化を機械学習モデルの教師データとして用いて，実際の盛土の安定性を評価する簡便法を提案し，その有効性を示し本研究を総括している．This study aims to investigate the mechanical behavior of embankments constructed
from volcanic soil under the independent and combined effect of r ainfall and seismic
loadings. To accomplish this purpose, a series of 1g model experiments on embankments
were conducted with an apparatus that integrated both the spray nozzle and the shaking
table. The soil samples were prepared using Komaoka volcanic co arse grained soils as
materials with 3 different amounts of fine particle contents while the initial water
content was chosen at dry cases and wet cases of optimum water content. In the
experiments, shear strain, acceleration, pore water pressure, and satu ration degree were
monitored and measured to provide an understanding of the influence of different fine
particle contents and initial water content on the failure mechanism of the volcanic
embankment subjected to rainfall and earthquake. In post rainfall earthquake tests, the
seismic loadings were applied at 3 different conditions of pore water pressure inside the
embankments to clarify the effect of dissipation time between rainfall and earthquake.
The results of post rainfall earthquake cases in this stu dy were compared with those in
the cases of post earthquake rainfall in previous research to investigate the importance
of the order impact of external forces. The physical model test results were also compared
with previous research including element test s and disaster reports. Besides, modern
techniques of artificial intelligence were applied to predict the water retention
characteristic.
The results show that the previous rainfall plays an important role in evaluating the
stability of embankments under subsequent earthquakes through water retention
conditions inside the slope such as rainfall induced residual pore water pressure and
satura tion degree. The fine particle content has a great influence and must be taken into
account when studying the stability of the volcanic embankment under the independent
or combined effects of rainfall and earthquake. At the same degree of compaction, the
p ermeability of volcanic soils decreases with the increase in the fine grains content. The
earthquake resistance of the compacted volcanic embankments subjected to previous
rainfall increases as the fine content increase. Even so, this increment in seismic
strength is not significant when the fines content was higher than 27%. Initial water
content has a great influence on the mechanical behavior, infiltration characteristics,
and failure phenomenon of embankments due to rainfall and/or earthquakes. The perm
eability of the compacted soil on the wet side of the optimum moisture content is
less than it is on the dry side when the fine grain content of the soil is sufficiently large.
In contrast, embankments compacted on the wet side exhibit less resistance to
s ubsequent earthquakes under the same shear strain due to previous rainfall. When
embankments are subjected to dual disasters, the slope stability may be various for
different orders of earthquake and rainfall even though the preceding received shear
strain is similar. Finally, a simple method to evaluate slope stability in practice with the
measured water content as the object of assessment was proposed based on the change
in soil infiltration capacity. Machine learning models can be applied to predict pore water
pressure values from historical data. Daily updates of the dataset and the climate data
can significantly improve prediction accuracy.doctoral thesi
Prediction accuracy of Random Forest, XGBoost, LightGBM, and artificial neural network for shear resistance of post-installed anchors
Get PDFP ost installed anchors and reinforcing bars are used to connect equipment or to fasten
strengthening members to re i nforced concrete ( structures For safety reasons , a ppropriate struc-
tural design is critical . Recently, artificial intelligence (AI) and machine learning (ML) have been
applied in various fields. According to previous studies , the bending strength of the RC beam and the
bond strength of the surface can be predicted using ML. In this study, the mechanical behavior of
post installed anchor s s ubjected to shear force were predicted using ML. F our algorithms were ap-
plied in this study : R andom F orest (RF), XG B oost (XB), L ightGBM (LG), and an a rtificial neural
network ( A NN). Moreover, the authors’ previous test results were used for the ML and testing . The
number of specimens was t hirty two . The test parameters were the concrete compressive strength f c ,
diameter of the anchor bolt d d , type of adhesive, and tensile ratio r N . The values for f c and d d were set
at 13.0 35.5 N/mm 2 and 1 3 25 mm, respectively. In this study, o ne epoxy adhesive and three cement
based adhesive s were used . r N , which is the ratio o f the tensile stress to yield strength of the anchor
bolt, was set to 0, 0.33, and 0.66. Consequently , the four algorithms could accurately predict the me-
chanical behavior of the specimen when the parameters were within or close to the training data.
However, the prediction agreements of RF, XB, and LG were not good for the behavior of specimen s
whose parameters were not included i n the training data. Nevertheless , the A NN was able to rea-
sonably predict the behavior of the se case s I t was concluded that the four algorithms can make good
predictions when the parameters are within or close to the training data. However, when parameters
outside the training data were used , the A NN was the best of the four algorithms used in this studyjournal articl
Significant changes in thermoelectric properties of unfilled skutterudite compounds MSb3 (M = Co and Rh) by self-insertion reaction
Get PDFjournal articl
A Data-Driven Automatic Design of Induction Motors Based on Tree Search and Reinforcement Learning Considering Multiple Objectives
Get PDFThe design problems of electric machines are mixed-integer ones, which are generally difficult to solve.
To automatically obtain whole designs of electric machines, in this paper, a multi-objective automatic design method for electric machines is presented based on the tree search-based reinforcement learning and multi-fidelity technique.
In this method, various candidate designs are generated based on the tree search using low-fidelity model.
The value functions of the nodes are learned from the generated data. Moreover, high-fidelity evaluations are applied to a limited number of better designs, and then, the multi-fidelity metamodel is constructed to correct the lowfidelity evaluation results.
The present method is applied to the design problem an induction motor.
It is shown that various designs are obtained considering trade-off relation between two objectives based on high-accuracy evaluations.journal articl
フライアッシュおよび高炉スラグ微粉末を用いたコンクリートの凍害との複合劣化に関する研究
Get PDF室蘭工業大学Muroran Institute of Technology博士（工学）application/pdf一般的に、構造物に生じている劣化原因を一つに特定できない、すなわち複合劣化と呼ばれる劣化現象が多くみられるようになっている。この場合では各劣化現象の相互作用によって、発生した劣化形態が複雑で、単一の劣化モデルを足し合わせてその複雑劣化評価を行うことができない。一方、環境負荷低減の観点からセメント生産時に発生するCO2の削減や産業副産物の有効利用が求められ、セメント由来のCO2を削減することができる高炉（BFS）セメントおよびフライアッシュ（FA）セメントの研究が進められてきた。この背景として、寒冷地において、凍害が特色で、BFSやFAを用いたコンクリートの凍害の複合劣化に対する関心が高まりつつあり、検討する必要がある。凍害と塩害の複合劣化については多くの既往研究があるが、中性化と凍害やアルカリ骨材反応（ASR）と凍害の複合劣化に関する報告は少ない。ここで、本研究では、BFSやFAを用いたコンクリートの性化と凍害や凍害とASRの複合劣化の劣化機構を把握していく。1. NonAEでは、中性化により、OPCと低置換率のBFSコンクリートの耐凍害性が低下しているが、高置換率のBFS簿耐凍害性が向上している。BFSの添加により、Non-AEコンクリートで、中性化後の耐凍害性は低下しているが、AEコンクリートで、中性化後の耐凍害性は低下していない。2． FAコンクリートについて、中性化による耐凍害性が変化していない。吸水率に比べ、コンクリートの耐凍害性やスケーリングが細孔構造とのの関係は認められる。FAの添加により、Non-AEコンクリートで、中性化後の耐凍害性は低下しているが、AEコンクリートで、中性化後の耐凍害性は低下していない。3．OPCコンクリートでは、先行のASRにより、凍害を促進したが、先行の凍害により、ASRによる膨張を促進抑制された。BFSやFAコンクリートで、凍害に関わらず、ASRの膨張を大幅に減らされた。BFSやFAの混入により、ASRを抑制することで、ひび割れの発生も少なく、ASR後の耐凍害性を向上したことが確認できた。実環境下で、JIS規格により、AEコンクリートの使用は普通としている。CO2の削減するために、環境負荷低減リサイクル材とするBFSやFAの推進するとともに、コンクリートの長期強度など改善されられる。一方、BFSやFAの使用は塩害や中性化したコンクリートの耐凍害性を変化していなくて、さらにASRを受けたコンクリートの耐凍害性を向上できる。複合劣化の観点から、建築分野で、BFSやFAの使用を広く普及することを提案した。For concrete structures in cold regions, the frost damage often occurs in the winter construction of concrete, which seriously threatens the performance and structural safety of concrete. The other concrete deteriorations such as salt damage, carbonation, and alkali-silica reaction (ASR) are also related closely to the durability of concrete. So far, the single deterioration mechanism is mainly studied in almost previous studies and the results have been accumulated substantially. However, for the actual concrete structures, it is not possible to suffer a single deterioration only. On the hand, in recent years, in the trend of CO2 emission reduction, blast furnace slag (BFS) and fly ash (FA) are used more widely to reduce the cement consumption in the field of building materials.Therefore, this study will investigate the combined deterioration between carbonation and frost damage, and ASR and frost damage of concrete containing BFS and FA, the effect on the combined deterioration would be also made clear.1. For Non-AE BFS concrete, carbonation can reduce the frost resistance of OPC concrete and BFS concrete with a low replacement ratio but can improve the frost resistance of BFS concrete with a high replacement ratio. For AE BFS concrete, the frost and scaling resistance of all concrete is kept at a high level. The additive of BFS can reduce the frost resistance of Non-AE concrete subjected to carbonation, and has no effect on frost resistance of AE concrete.2. For FA concrete, carbonation has little effect on the frost resistance of concrete. Besides, the frost and scaling resistance are far more reliant on the changes in pore structure than they are on the water absorption. Due to additive of FA, the frost and scaling resistance of AE concrete subjected to carbonation is kept at a high level; while, for Non-AE concrete subjected to carbonation, the frost and scaling resistance tends to decrease.3. for OPC concrete, expansion due to ASR could be restrained when subjected to freeze-thaw, and frost resistance is reduced when subjected to ASR. For BFS and FA concrete, expansion due to ASR could be restrained regardless of being subjected to frost damage. The additive of BFS and FA can improve the frost resistance of concrete subjected to ASR. In real environment, AE concrete is used wildly for concrete construction. Therefore, in the study, it can be obtained that the use of BFS and FA don’t reduce of frost resistance of concrete subjected to salt damage and carbonation and increase the frost resistance of concrete subjected to ASR. Overall evaluation, the use of BFS and FA are beneficial to the safety of concrete.doctoral thesi
記憶法で漢字の意味と書き方を覚える
Get PDFThis paper will explore cognitive differences that can be attributed to the different orthographic systems used in English and Japanese, and then examine how a mnemonic technique could be used to exploit these differences. Heisig’s mnemonic system for remembering the writing and meaning of Chinese characters (Kanji) is a Component Analysis method style of learning that attempts to create an alphabet of Kanji elements that can be used to both construct (write) and deconstruct (translate) Kanji. This has the potential to help prevent English-speaking students of Japanese from losing interest and motivation. A technique involving anthropomorphizing elements of the Kanji to help make the mnemonic stories more memorable will also be explored, using examples from the author’s own learning journey.journal articl